touch.js

//>>excludeStart("jqmBuildExclude", pragmas.jqmBuildExclude);
//>>description: Touch events including: touchstart, touchmove, touchend, tap, taphold, swipe, swipeleft, swiperight, scrollstart, scrollstop
//>>label: Touch
//>>group: Events

define( [ "jquery", "../jquery.mobile.vmouse", "../jquery.mobile.support.touch" ], function( jQuery ) {
//>>excludeEnd("jqmBuildExclude");

(function( $, window, undefined ) {
	var $document = $( document ),
		supportTouch = $.mobile.support.touch,
		scrollEvent = "touchmove scroll",
		touchStartEvent = supportTouch ? "touchstart" : "mousedown",
		touchStopEvent = supportTouch ? "touchend" : "mouseup",
		touchMoveEvent = supportTouch ? "touchmove" : "mousemove";

	// setup new event shortcuts
	$.each( ( "touchstart touchmove touchend " +
		"tap taphold " +
		"swipe swipeleft swiperight " +
		"scrollstart scrollstop" ).split( " " ), function( i, name ) {

		$.fn[ name ] = function( fn ) {
			return fn ? this.bind( name, fn ) : this.trigger( name );
		};

		// jQuery < 1.8
		if ( $.attrFn ) {
			$.attrFn[ name ] = true;
		}
	});

	function triggerCustomEvent( obj, eventType, event, bubble ) {
		var originalType = event.type;
		event.type = eventType;
		if ( bubble ) {
			$.event.trigger( event, undefined, obj );
		} else {
			$.event.dispatch.call( obj, event );
		}
		event.type = originalType;
	}

	// also handles scrollstop
	$.event.special.scrollstart = {

		enabled: true,
		setup: function() {

			var thisObject = this,
				$this = $( thisObject ),
				scrolling,
				timer;

			function trigger( event, state ) {
				scrolling = state;
				triggerCustomEvent( thisObject, scrolling ? "scrollstart" : "scrollstop", event );
			}

			// iPhone triggers scroll after a small delay; use touchmove instead
			$this.bind( scrollEvent, function( event ) {

				if ( !$.event.special.scrollstart.enabled ) {
					return;
				}

				if ( !scrolling ) {
					trigger( event, true );
				}

				clearTimeout( timer );
				timer = setTimeout( function() {
					trigger( event, false );
				}, 50 );
			});
		},
		teardown: function() {
			$( this ).unbind( scrollEvent );
		}
	};

	// also handles taphold
	$.event.special.tap = {
		tapholdThreshold: 750,
		emitTapOnTaphold: true,
		setup: function() {
			var thisObject = this,
				$this = $( thisObject ),
				isTaphold = false;

			$this.bind( "vmousedown", function( event ) {
				isTaphold = false;
				if ( event.which && event.which !== 1 ) {
					return false;
				}

				var origTarget = event.target,
					timer;

				function clearTapTimer() {
					clearTimeout( timer );
				}

				function clearTapHandlers() {
					clearTapTimer();

					$this.unbind( "vclick", clickHandler )
						.unbind( "vmouseup", clearTapTimer );
					$document.unbind( "vmousecancel", clearTapHandlers );
				}

				function clickHandler( event ) {
					clearTapHandlers();

					// ONLY trigger a 'tap' event if the start target is
					// the same as the stop target.
					if ( !isTaphold && origTarget === event.target ) {
						triggerCustomEvent( thisObject, "tap", event );
					} else if ( isTaphold ) {
						event.stopPropagation();
					}
				}

				$this.bind( "vmouseup", clearTapTimer )
					.bind( "vclick", clickHandler );
				$document.bind( "vmousecancel", clearTapHandlers );

				timer = setTimeout( function() {
					if ( !$.event.special.tap.emitTapOnTaphold ) {
						isTaphold = true;
					}
					triggerCustomEvent( thisObject, "taphold", $.Event( "taphold", { target: origTarget } ) );
				}, $.event.special.tap.tapholdThreshold );
			});
		},
		teardown: function() {
			$( this ).unbind( "vmousedown" ).unbind( "vclick" ).unbind( "vmouseup" );
			$document.unbind( "vmousecancel" );
		}
	};

	// also handles swipeleft, swiperight
	$.event.special.swipe = {
		scrollSupressionThreshold: 30, // More than this horizontal displacement, and we will suppress scrolling.

		durationThreshold: 1000, // More time than this, and it isn't a swipe.

		horizontalDistanceThreshold: 30,  // Swipe horizontal displacement must be more than this.

		verticalDistanceThreshold: 75,  // Swipe vertical displacement must be less than this.

		start: function( event ) {
			var data = event.originalEvent.touches ?
					event.originalEvent.touches[ 0 ] : event;
			return {
						time: ( new Date() ).getTime(),
						coords: [ data.pageX, data.pageY ],
						origin: $( event.target )
					};
		},

		stop: function( event ) {
			var data = event.originalEvent.touches ?
					event.originalEvent.touches[ 0 ] : event;
			return {
						time: ( new Date() ).getTime(),
						coords: [ data.pageX, data.pageY ]
					};
		},

		handleSwipe: function( start, stop, thisObject, origTarget ) {
			if ( stop.time - start.time < $.event.special.swipe.durationThreshold &&
				Math.abs( start.coords[ 0 ] - stop.coords[ 0 ] ) > $.event.special.swipe.horizontalDistanceThreshold &&
				Math.abs( start.coords[ 1 ] - stop.coords[ 1 ] ) < $.event.special.swipe.verticalDistanceThreshold ) {
				var direction = start.coords[0] > stop.coords[ 0 ] ? "swipeleft" : "swiperight";

				triggerCustomEvent( thisObject, "swipe", $.Event( "swipe", { target: origTarget, swipestart: start, swipestop: stop }), true );
				triggerCustomEvent( thisObject, direction,$.Event( direction, { target: origTarget, swipestart: start, swipestop: stop } ), true );
				return true;
			}
			return false;

		},

		// This serves as a flag to ensure that at most one swipe event event is
		// in work at any given time
		eventInProgress: false,

		setup: function() {
			var events,
				thisObject = this,
				$this = $( thisObject ),
				context = {};

			// Retrieve the events data for this element and add the swipe context
			events = $.data( this, "mobile-events" );
			if ( !events ) {
				events = { length: 0 };
				$.data( this, "mobile-events", events );
			}
			events.length++;
			events.swipe = context;

			context.start = function( event ) {

				// Bail if we're already working on a swipe event
				if ( $.event.special.swipe.eventInProgress ) {
					return;
				}
				$.event.special.swipe.eventInProgress = true;

				var stop,
					start = $.event.special.swipe.start( event ),
					origTarget = event.target,
					emitted = false;

				context.move = function( event ) {
					if ( !start ) {
						return;
					}

					stop = $.event.special.swipe.stop( event );
					if ( !emitted ) {
						emitted = $.event.special.swipe.handleSwipe( start, stop, thisObject, origTarget );
						if ( emitted ) {

							// Reset the context to make way for the next swipe event
							$.event.special.swipe.eventInProgress = false;
						}
					}
					// prevent scrolling
					if ( Math.abs( start.coords[ 0 ] - stop.coords[ 0 ] ) > $.event.special.swipe.scrollSupressionThreshold ) {
						event.preventDefault();
					}
				};

				context.stop = function() {
						emitted = true;

						// Reset the context to make way for the next swipe event
						$.event.special.swipe.eventInProgress = false;
						$document.off( touchMoveEvent, context.move );
						context.move = null;
				};

				$document.on( touchMoveEvent, context.move )
					.one( touchStopEvent, context.stop );
			};
			$this.on( touchStartEvent, context.start );
		},

		teardown: function() {
			var events, context;

			events = $.data( this, "mobile-events" );
			if ( events ) {
				context = events.swipe;
				delete events.swipe;
				events.length--;
				if ( events.length === 0 ) {
					$.removeData( this, "mobile-events" );
				}
			}

			if ( context ) {
				if ( context.start ) {
					$( this ).off( touchStartEvent, context.start );
				}
				if ( context.move ) {
					$document.off( touchMoveEvent, context.move );
				}
				if ( context.stop ) {
					$document.off( touchStopEvent, context.stop );
				}
			}
		}
	};
	$.each({
		scrollstop: "scrollstart",
		taphold: "tap",
		swipeleft: "swipe",
		swiperight: "swipe"
	}, function( event, sourceEvent ) {

		$.event.special[ event ] = {
			setup: function() {
				$( this ).bind( sourceEvent, $.noop );
			},
			teardown: function() {
				$( this ).unbind( sourceEvent );
			}
		};
	});

})( jQuery, this );
//>>excludeStart("jqmBuildExclude", pragmas.jqmBuildExclude);
});
//>>excludeEnd("jqmBuildExclude");